1. You can try to run the MCPR tool. from link below
2. Restart the computer
3. Open Internet explorer, Click on Tools, Internet Options -> Advanced -> Reset
4. Ran the Pitool from the link below
5. If you are using Windows Vista or Windows 7 restart the computer else if you are using Windows XP go to step 6
6. Try to download McAfee again..
Revert back if the same problem occurs.
Thank you for the help!
I'm afraid to say even after I followed your instructions, I'm getting the same error message from the McAfee installer. (Would it have something to do with the fact I use Firefox instead of Internet Explorer?)
Do you think it may not be installing because I also have Spybot - Search and Destroy and Malwarebytes' Anti-Malware?
The other antivirus software can make the Download Manager unable to access the Internet.
I would suggest you to uninstall the other security softwares from control panel as well as its files and folders from C:\program files and common files.
Restart the computer and tap pressing the F8 keys while restarting , from Windows advanced boot menu select safe mode with networking. (Ignore this step if you are on a wireless connection)
Then Try installing again,